Has excellent on-axis sharpness and superb contrast. In an f5.4 reflector and f6.6 refractor, edge sharpness was not as good as a 12.5mm Celestron Ultima. Edge sharpness is not a problem, I hear, in longer f-ratio scopes - nor is it a problem with the 5mm and 7.5mm Tak LE.
Another great eyepiece from Takahashi. The clarity and overall contrast are superb. The image is perfect even out to the edge of the field. The reason it did not get a perfect 10 is that the eye relief is still only 9mm or so, and that is the same as any other plossl. However, do not confuse the quality of image of this LE with any other plossl, for it is the best of the best. I make these comments based on over a years observation through an f/10 or f/6.3 with (reducer) SCT and an f/10 90mm refractor.
Awesome Eye relief, They dont get any Better this This!
I have used both the 5mm and 7mm Tak LEs on many different scope types, preferring both for higher powers over the Naglers and Radians. I would be hard pressed not to give the LEs a slight advantage for both their optical excellence and overall performance. But what I notice most of all, wheather Ive used this piece in a Large SCT, Refractor or my Dall Kirkham is that this piece allows you to enjoy each object you choose to look at the more you concentrate on a particular object either deep sky or planetary. The 12.5mm is no different, with its Awesome Eye Relief, They dont get much Better then this!
Elk Grove CA